Load ejection improvement for self-loading scrapers

ABSTRACT

A control system for the hydraulically powered .Iadd.conveyor, such as an .Iaddend.auger.Iadd., .Iaddend.of a self-loading .[.auger.]. scraper that has an ejector operated by a hydraulic cylinder. One manual control valve starts and stops the auger in conjunction with loading. A second manual control valve powers the ejector cylinder and simultaneously operates a valve to start the auger independently of the first manual control valve.

BACKGROUND OF THE INVENTION

Self-loading .[.auger.]. scrapers .Iadd.with a conveyor such as an auger.Iaddend.have complex hydraulic systems with a large number of controlsat the operator's cab, and in order to minimize the complexity of theoperation it is desirable to combine controls where it is practical todo so. The operator must, of course, be able to move the scraper bowlbetween an elevated road position and a lower loading and unloadingposition. There is also a control for the bowl apron which closes thefront of the bowl when a load is being transported and which is movedfor loading and unloading. The auger must operate during loading, and inthe case of a fixed auger must also operate during unloading. There isalso a pitch and bounce control which should be operative when the unitis in transport mode but which must be locked out for loading andunloading.

A multiple function scraper control valve includes a control handle formanually shifting the valve to operate the ejector. Under mostconditions it is essential that the auger operate when the ejector isoperating, because otherwise the ejector will jam material into theauger instead of unloading it through the auger.

In order to minimize the number of controls that the operator must use,it is desirable to provide for operation of the auger when the ejectorcontrol handle is moved from a first position to a second position forpowering the ejector cylinder.

SUMMARY OF THE INVENTION

.Iadd.The hydraulic control system of the present invention is shown anddescribed as controlling the operation of a rotary hydraulic motor. Inthe specific embodiment shown the motor drives an auger conveyor thatserves as a loading assist for the bowl of a self-loading scraper..Iaddend.

In accordance with the present invention, the control for augeroperation includes a drain line which is open to the reservoir when theauger is not operating, and which must be closed to cause fluid from anauger pump to go to an auger hydraulic motor instead of returning to thereservoir.

There are two normally open valves in the drain line in series. Thefirst of the normally open valves is closed in response to movement ofthe manual control member for the ejector mechanism from its firstposition to a second position for powering the ejector cylinder. Thesecond normally open valve is a pilot operated valve to which operatingfluid is selectively admitted by operation of a manual pilot selectorvalve of the type disclosed in U.S. Pat. No. 3,618,984. The primaryauger operating control initiates auger operation in conjunction withloading of the scraper bowl, and shifting of the manual pilot selectorvalve is what controls auger operation under those conditions.

The primary auger control system also includes an unloading relief valvewhich is normally open so that fluid from auger pump means returns tothe reservoir. The unloading relief valve is controlled by a signal linethat is normally open to drain through the second normally open valve inthe drain line. Closing of said second normally open valve isolates thesignal line from the drain line, closing the unloading relief valve andcausing fluid from the auger pump means to go through a conduit to theauger motor.

The first normally open valve of the present system is a solenoidoperated valve, and the energizing circuit for the solenoid includes anormally open limit switch which is closed by movement of the manualcontrol handle for ejector hydraulic circuit.

THE DRAWINGS

FIG. 1 is a side elevational view, partly in section, of a self-loadingauger scraper;

FIG. 2 is a hydraulic circuit diagram of that portion of the hydrauliccircuit which relates to operation and control of the auger; and

FIG. 3 is a hydraulic schematic view of the unloading relief valve usedin the control circuit.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, the apparatus of the present invention consistsgenerally of a tractor 10 to which a scraper 11 is connected by means ofa conventional gooseneck 12. The scraper 11 includes a bowl 13 having afloor 14 and sidewalls 15, and a cross beam 16 between the upper ends ofthe sidewalls cooperates with the bowl floor 14 in mounting an augerassembly, which is indicated generally at 17 and has its lower end closeto a forward cutting edge 18 of the bowl. The scraper is illustrated asprovided with ejector means, indicated generally at 19, of the typedisclosed and claimed in patent 3,863,367.

The auger assembly 17 consists generally of a supporting bearingassembly, indicated generally at 20, which is secured to the bowl floor14; auger drive means 21 which is mounted upon the top cross beam 16;and an auger, indicated generally at 22.

In addition to the scraper bowl and auger components illustrated in FIG.1, the apparatus is to be understood as including a cushion hitchstructure of the type disclosed in U.S. Pat. No. 3,311,389.

Turning now to FIGS. 2 and 3, the hydraulic operating and controlcircuit for a hydraulic motor 23 of the auger drive means 21 includes ahydraulic fluid reservoir 24; a manual pilot selector valve 25 of thekind disclosed in patent 3,618,984; a large auger pump 26 having acapacity of 60 gallons per minute and which is coupled with a cushionhitch pump 27 that has a capacity of 8 gallons per minute; a small augerpump 28 that delivers 21 gallons per minute and is coupled with a 60gallon per minute scraper pump 29 that is not part of the augeroperating and control system; a relief and unloading valve 30; and anormally open, pilot operated auger control valve 31; together with thenecessary pipes and conduits between the foregoing components, thehydraulic motor 23 and the reservoir 24.

As disclosed in patent 3,618,984, the manual pilot selector valve 25 isa spool valve which has an operating handle 25a that is movable betweenthe A position shown in FIG. 2, a B position, and a C position. In the Aposition of the pilot selector valve 25 a cushion hitch means, indicatedgenerally at 32, is in a transport mode as disclosed in patent3,311,389, and the auger motor 23 is idle. In the B position, inaccordance with the teachings of patent 3,618,984, the cushion hitch isdeactivated with the cushion hitch locked in a bottomed out position astaught in patent 3,311,389, and the auger motor 23 is still idle. In theC position of valve 25 the cushion hitch is still locked down and theauger motor 23 is powered from the pumps 26 and 28 to drive the auger.

The B position of the valve 25 is rarely used, because ordinarily thecushion hitch is lowered and locked only for loading or unloading, andin those situations the auger motor 23 should be driving. However, thereare occasional situations when the operator may want to lock down thecushion hitch when the apparatus is in its transport mode so as toafford the maximum possible control over a loaded vehicle being operaedunder difficult driving conditions.

A fluid conduit 33 and a branch conduit 34 connect the reservoir 24 withthe low pressure sides of the pumps 26, 27, 28 and 29. The high pressuresides of the pumps 26 and 28 connect with the unloading relief valve 30through respective lines 35 and 36; and as illustrated in FIG. 3, thevalve 30 is normally open to the reservoir 24 through a manifold 37 anda drain conduit 38. Thus, the output of the auger pumps 26 and 28 isunloaded to the reservoir in the A position of the manual pilot selectorvalve 25.

Control of the unloading relief valve 30 is by means of a signal conduit39 which is joined exteriorly of the valve 30 by a signal conduit 39a sothat, in effect, the two signal conduits act as one in the control ofthe valve 30. The signal line 39 is connected through the normally openauger control valve 31 to a return line 40 which drains directly to thereservoir 24 through a drain line 41 which also may receive fluid from aconventional leakage drain line 42 connected to the valve 31.

A pilot line 43 for the valve 31 is connected to the manual pilotselector valve 25, and in the A position of the pilot selector valve thepilot line 43 is in communication with a drain line 44 through whichfluid from the valve 25 returns to the reservoir 24.

Also, in the A position of the pilot selector valve 25 the output of thepump 27 is delivered through a line 45 to a filter 46 from which theprincipal flow goes through a line 47 to a normally closed control valve48 for the cushion hitch cylinder 32. The balance of the flow from thefilter 46 goes through a line 49 to the pilot selector valve 25, andfrom there through a pilot line 50 the pressure from which keeps thenormally closed valve 48 open as long as the pilot selector valve 25 isin the A position.

When the pilot selector valve is moved to the B position, the fluid fromthe line 49 is isolated from the pilot line 50 and returns through thedrain line 44 to the reservoir 24. In this position of the pilotselector valve the condition of the auger control valve 31 remainsunchanged.

When the pilot selector valve 25 is moved to the C position, itterminates communication between the pilot line 43 and the drain line 44and places the line 49 from the cushion hitch pump 27 into communicationwith the pilot line 43 so as to close the valve 31. This blockscommunication between the signal lines 39-39a and the return line 40 anddrain line 41 and causes the unloading relief valve 30 to breakcommunication between the lines 35 and 36 and the drain line 38. Theoutput from the auger pump 28 through the line 36 to the valve 30 isshifted within the valve to the line 35, as indicated by the reversearrows in that line; so the output from the pump 28 combines with thatof the pump 26 and goes through a drive conduit 51 to the auger motor 23from which the fluid returns to the reservoir 24 through several lineswhich are numbered collectively 52.

The output from the scraper pump 29 goes to a multiple function scrapercontrol valve, indicated generally at 53, which is provided with ascraper control handle 54, an apron control handle 55, and an ejectorcontrol handle 56. A first conduit 57 of a group of conduits carriesfluid from the control valve 53 to an ejector cylinder 19a (FIG. 1),while others of said group of conduits take fluid to a bowl cylinder orto an apron cylinder, depending upon the positions of the manualcontrols 54, 55 and 56.

The manual control 56 has a first position in which no fluid is suppliedto the ejector cylinder 19a, and a second position in which fluid issupplied through the line 57.

Simultaneous control of the power to the auger motor 23 and to theejector cylinder 19a is by means of a normally open solenoid valve 58which is in the drain line 40, and a solenoid energizing circuit 59which includes a normally open limit switch 60 that is located inoperative relationship to the ejector control handle 56. Movement of thecontrol handle 56 from its first position to its second positionmechanically closes the limit switch 60 to energize the solenoid of thevalve 58 and close said valve for the purpose of isolating the signalline 39 from the drain line 41, even though the auger control valve 31is still open.

Thus, the normally open pilot operated auger control valve 31 and thenormally open solenoid valve 58 are positioned in series in the drainline 40-41 so that closing of either valve causes the unloading reliefvalve 30 to be closed and thus causes fluid under pressure to go fromthe pumps 26 and 28 to the auger motor 23.

The foregoing detailed description is given for clearness ofunderstanding only and no unnecessary limitations should be understoodtherefrom as modifications will be obvious to those skilled in the art.

What is claimed is:
 1. In a self-loading auger scraper that includes ascraper bowl, a generally upright auger mounted in the forward portionof the bowl, a hydraulic motor for driving the auger, an ejectormechanism including a generally upright ejector member and a hydrauliccylinder for reciprocating the ejector member between the rear of thebowl and the front of the bowl, a fluid reservoir, first pump means forsupplying fluid under pressure from the reservoir to the ejectorcylinder, second pump means for supplying fluid under pressure from saidreservoir to the auger motor, and a control system that includes a firstmanually actuated valve for directing the output of said second pumpmeans selectively to the auger motor or to the reservoir and a secondmanually actuated valve which is movable between a first position inwhich fluid from the first pump is blocked from the ejector cylinder anda second position in which such fluid flows to said cylinder to move theejector member, means for driving the auger when the ejector member isoperated comprising, in combination:a drain line which is open to thereservoir when the auger motor is idle and which is closed to cause theoutput of the second pump means to be directed to the auger motor; afirst normally open valve in said drain line; and means controlled bymovement of the second manually actuated valve from its first positionto its second position for closing said normally open valve.
 2. Thecombination of claim 1 in which the normally open valve is solenoidoperated, and the means controlled by movement of the second manuallyactuated valve comprises a normally open switch in an energizing circuitfor said solenoid, and means for closing said switch in response tomovement of said second manually actuated valve.
 3. The combination ofclaim 2 in which the switch is a limit switch and the means for closingsaid switch is mounted on the manual actuator for the second valve. 4.The combination of claim 1 in which the control system for the augermotor includes a normally open, pilot operated auger control valve, anunloading valve which is normally open to connect the second pump meansto the reservoir and which has a signal line that is open to said drainline through said pilot operated valve, in which the first manuallyactuated valve is a pilot selector valve which is movable from a firstposition to a second position to pressurize a pilot line for said augercontrol valve, and thereby close said valve to isolate said signal linefrom the drain line and thus close the unloading valve, the normallyopen valve in the drain line being in series with said normally openauger control valve.
 5. The combination of claim 1 which includes asecond normally open valve in the drain line in series with the firstnormally open valve in said line, and an operative connection betweensaid first manually actuated valve and said second normally open valveto close the latter valve upon manual actuation of the former valve..Iadd.
 6. In a self-loading scraper that includes a scraper bowl, agenerally upright loading assist mounted in the forward portion of thebowl, a hydraulic motor for driving the loading assist, an ejectormechanism including a generally upright ejector member and a hydrauliccylinder for reciprocating the ejector member between the rear of thebowl and the front of the bowl, a fluid reservoir, first pump means forsupplying fluid under pressure from the reservoir to the ejectorcylinder, second pump means for supplying fluid under pressure from saidreservoir to the hydraulic motor, and a control system that includes afirst manually actuated valve for directing the output of said secondpump means selectively to the hydraulic motor or to the reservoir and asecond manually actuated valve which is movable between a first positionin which fluid from the first pump is blocked from the ejector cylinderand a second position in which such fluid flows to said cylinder to movethe ejector member, means for driving the loading assist when theejector member is operated comprising, in combination:a drain line whichis open to the reservoir when the hydraulic motor is idle and which isclosed to cause the output of the second pump means to be directed tothe hydraulic motor; a first normally open valve in said drain line; andmeans controlled by movement of the second manually actuated valve fromits first position to its second position for closing said normally openvalve. .Iaddend.